Iranian Foreign Minister Mohammad Javad Zarif and Russian President Vladimir Putin have underlined the need for all parties to Iran’s nuclear agreement, known as the Joint Comprehensive Plan of Action (JCPOA), to fulfill their commitments stipulated in the deal.

Zarif, who arrived in the Russian city of Sochi on Wednesday, met and exchanged views with President Putin on matters of mutual interest. Russian Foreign Minister Sergei Lavrov also attended the meeting.

Speaking to reporters following the meeting, the top Iranian diplomat described his talks with the Russian leader as “substantial and positive.”

Regarding the JCPOA, it was stressed that the deal is non-negotiable and that all sides to the agreement must fulfill their obligations, the Iranian foreign minister said.

“The Islamic Republic of Iran has so far fulfilled all its commitments concerning the JCPOA, but unfortunately certain sides have not stayed committed as they should. Today, we stress that this (the JCPOA) is an international and multilateral agreement and that all sides should adhere to it,” he added.

Zarif added that he also discussed the Syrian crisis with the Russian president, stressing Moscow and Tehran have had good cooperation in the battle against terrorism.

The Iranian foreign minister said that Iran, Russia and Turkey are due to continue talks on Syria in the Kazakh capital Astana to discuss ways to restore peace to the Arab country, deliver humanitarian aid and initiate a political process aimed at resolving the country's crisis.

Zarif said that the two sides also discussed the expansion of ties in different fields, including cooperation in the defense, nuclear energy, transportation and energy sectors.

Lavrov also told reporters that Iran has kept its side of the bargain in implementing the JCPOA.

Iran and the five permanent members of the United Nations Security Council – the United States, France, Britain, Russia and China – plus Germany signed the JCPOA on July 14, 2015 and started implementing it on January 16, 2016.

Under the JCPOA, Iran undertook to put limitations on its nuclear program in exchange for the removal of nuclear-related sanctions imposed against Tehran.

On Monday, the director general of the International Atomic Energy Agency, Yukiya Amano, said Iran was abiding by the rules set out in the nuclear accord it signed with the P5+1 group of countries.

“The nuclear-related commitments undertaken by Iran under the (deal) are being implemented,” Amano said in the text of a speech to the Board of Governors.